JSSC 2023第7期Other

A Baseline-Tracking Single-Channel I/Q Impedance Plethysmogram IC for Neckband-Based Blood Pressure and Cardiovascular Monitoring Chan Sam Park , Student Member , IEEE, Hyunjoong Kim , Student Member , IEEE

提出一种具有宽范围精细基线跟踪能力的阻抗体积描记IC，用于颈带式心血管监测。

145.2-dB DR, 103.5-dB SNR

阻抗体积描记基线跟踪心血管监测颈带设备连续血压测量

▸创新点1：混合模式基线消除方案（MM-BC）是一种方法创新，结合连续时间ΔΣ ADC进行高分辨率转换，实现了145.2-dB的动态范围和103.5-dB的SNR，显著提升了基线跟踪的精度和范围。

▸创新点2：相位同步器是一种电路创新，通过单通道实现I/Q检测功能，支持两电极和四电极配置，降低了系统复杂度和成本，同时保持了高性能。

▸创新点3：集成心电图（ECG）读取路径是一种系统创新，将IPG和ECG功能整合在同一芯片上，实现了多功能心血管监测，提升了系统的实用性和集成度。

▸创新点4：提出的IPG方案在颈带式可穿戴设备中实现了连续血压监测（基于脉搏到达时间PAT），并通过实验验证了其与参考血压设备的一致性，展示了系统级应用的可行性。

Abstract

An impedance plethysmogram (IPG) IC with wide-range ﬁne baseline tracking capability is proposed to provide continuous blood pressure (BP) and cardiovascular monitoring just by wearing a neckband wearable device. For the baseline tracking, a mixed-mode baseline cancellation (MM-BC) scheme is proposed to achieve wide dynamic range (DR) and high SNR performance, where an artifact-detecting continuous-time (CT)-/Delta1/Sigma1ADC is included together for high-resolution conversion. For cost-effective IPG design, a phase synchronizer concept is introduced to provide I/Q detection capability with single readout channel, supporting both conﬁgurations of two-electrode and four-electrode. A proposed readout integrated circuit (ROIC) prototype for the proposed IPG was fabricated, where an electrocardiogram (ECG) readout path is integrated together. The proposed IPG schemes were experimentally veriﬁed to achieve good performances of 145.2-dB DR and 103.5-dB SNR. For system-level feasibility, a neckband device prototype was also manufactured, and its cardiovascular monitoring functionality was functionally veriﬁed. Based on its IPG and ECG measure- ments, continuous BP measurement based on the pulse arrival time (PAT) was experimentally veriﬁed with a reference BP device.